1. Field of the Invention
This invention relates to coating plant seeds with a functional material which disintegrates after becoming wet to allow normal germination of the seeds.
2. Description of the Prior Art
It is known in the art to coat seeds with a functional material to provide protection against mechanical or environmental damage, and to use such coatings as a carrier for various materials such as, for example, fertilizer, pesticide, herbicide, etc. Such coatings have generally been of a water soluble material, so that the coating would dissolve to allow exposure of the seeds to the atmosphere for development. Such water soluble materials include water soluble polymers. Specifically U.S. Pat. No. 2,651,883 relates to use of polymeric water soluble polyelectrolytes as seed coatings. U.S. Pat. Nos. 3,707,807 and 3,598,565 relate to use of water soluble neutralized copolymer of an .alpha.,.beta.-unsaturated monocarboylic acid and a lower alkyl acrylate and a crosslinked copolymer of vinyl acetate and a lower alkyl acrylate. In contrast, U.S. Pat. No. 3,316,676 relates to a water insoluble seed coating, the integrity of which is destroyed by shrinkage due to contact with water. U.S. Pat. No. 3,905,152 relates to seeds having a coating thereon comprising non-porous, hydrophobic, non-phytotoxic particles which are adhered to each other and to the seed by means of a hydrophilic binder in such a manner that the coating is highly porous and provides facile gas and water exchange between the seed and the environment.